The FBI has cleared a federal agent in Boston in the fatal shooting of a friend of accused Boston Marathon bomber Tamerlan Tsarnaev last year in Orlando, according to two law enforcement officials familiar with the investigation.

The same officials said Friday that a Florida prosecutor conducting a separate investigation into the FBI shooting of Ibragim Todashev, 27, during an interrogation last May had also concluded that the agent committed no wrongdoing. But the prosecutor quickly denied that he had made a final decision.

A spokesman for state prosecutor Jeffrey L. Ashton said Ashton planned to review the investigative materials this weekend and make a decision by Monday. He had previously announced that he would release his final report on Tuesday.

“The State Attorney has not made a final decision regarding the investigation into the death of Mr. Todashev and he has not communicated his decision to any federal officials,” spokesman Richard Wallsh said in an e-mail.

The law enforcement officials spoke to the Globe on condition of anonymity because the reports still have not been released to the public. The Washington Post also reported that Ashton concluded Todashev’s shooting was justified.

The flurry of reports on Friday only intensified the frustration among those closely watching the case. Almost a year after the slaying, FBI and state officials have not said whether Todashev was armed or provided details of the alleged violent confrontation that prompted an agent to shoot and kill him in his own apartment. Investigators had been interrogating him about his friendship with Tsarnaev, one of the suspected Boston Marathon bombers.

On Friday, civil liberties groups and Todashev’s supporters complained about the pace of the investigation and urged state and federal investigators to release their records to the public.

“We still don’t know what happened,” said Carol Rose, executive director of the American Civil Liberties Union of Massachusetts. “Unless we have the documents that support those findings, mere conclusory statements aren’t really going to satisfy the public concern.”

Hassan Shibly, executive director of the Council on American-Islamic Relations in Florida, said he wanted to read the full reports. However, the council and other groups have repeatedly raised concerns about the FBI’s internal inquiry because documents obtained by The New York Times showed that the bureau rarely, if ever, faults agents for shootings.

In Chechnya, Todashev’s grieving father, Abdulbaki Todashev, said he was reluctant to comment without first reading the report. But he said he would be distressed if Ashton clears the agent.

“If it is really true, I will be horrified,” said Todashev, adding that he is on leave from the government in Chechnya, the southern region of Russia, as the investigation continues. “It will be terrible, because everything is self-evident here.”

Harvey Silverglate, a Boston criminal defense and civil liberties lawyer, called on the US House of Representatives or the Senate to investigate the case, saying only they had the authority to force federal officials to fully explain what happened.

“The whole thing is very odd from the beginning,” Silverglate said. “The bottom line is I didn’t expect the Florida prosecutor to say much because I didn’t expect him to learn much. What kind of power does he have to force the FBI or the [Department of Justice] to open up its records? You know the answer to that? Zero.”

Todashev’s family has insisted that he did nothing wrong and was too weakened by recent knee surgery to attack the armed agent. They have also pointed out that Todashev had voluntarily submitted to FBI questioning before agents showed up at his apartment that final time.

But Todashev also had fighting skills and a violent criminal record. The mixed-martial arts fighter was arrested in 2010 in Boston for a road-rage episode and again in Florida, weeks before he was killed, for allegedly beating a man in a fight over a parking space.

Florida and FBI officials have signaled for months that they were preparing to wrap up their separate investigations into whether the FBI agent’s use of deadly force was justified in the shooting of Todashev.

Ashton, who as state attorney is the top state prosecutor in Orlando, had said in December that he expected to release the information in early 2014. On March 6, he had asked media representatives to request interviews with him, in preparation for the likely release of the report.

In January, the FBI director said the bureau’s internal review had been finished for some time and he was eager to release the results as soon as the US Department of Justice’s civil rights division finished reviewing them. One of the law enforcement officials said Friday that the department is also expected to find that the agent committed no wrongdoing.

An FBI spokesman declined to comment Friday and referred questions to the state attorney’s office.

The ACLU of Massachusetts had also urged Massachusetts Attorney General Martha Coakley to investigate the case because two Massachusetts state troopers were at the shooting. Coakley, who is running for governor, declined to investigate, saying the matter was out of her jurisdiction.

A spokesman for the Coakley’s office said Friday that she would review the findings once they are released.

State Police spokesman David Procopio declined to comment.

Federal and state investigators tracked down Todashev as part of the investigation into Tamerlan Tsarnaev, one of two brothers who allegedly set off twin bombs on April 15 near the Marathon finish line. The bombs killed three people and injured more than 260 others.

Tsarnaev was killed several days later in a shootout with police in Watertown. His brother, Dzhokhar, is in federal custody facing a trial and possible death penalty.

The brothers also allegedly killed MIT Police Officer Sean Collier.

Media reports have also said that Todashev was about to sign a confession implicating himself and Tamerlan Tsarnaev in an unsolved triple homicide in Waltham. On Sept. 12, 2011, Brendan Mess, 24, who was a close friend of Tsarnaev, and two of his friends, Erik H. Weissman, 31, and Raphael M. Teken, 37, were found in Mess’s apartment with their throats slashed and bodies covered with marijuana.

At the time, their deaths were widely assumed to have been a drug deal gone sour.